Safe Data API — Requirement Specification

Software requirements for the Safe Data API (CONFIG_SAFE_DATA), a generic Zephyr facility for protecting variables and data structures with an integrity tag (CRC), an optional redundant inverted shadow copy, and a per-container mutex.

The specification is structured in two tiers:

• Top-level requirements (SD-TOP-…) state the guarantees of the safety function — what the API promises.

• Detailed requirements (SD-REQ-…) refine exactly one top-level requirement each (refines relation) — how the promise is delivered.

Every requirement is a sphinx-needs item with a stable ID. Test cases in the Test Specification link to the detailed requirements via their verifies relation; the Test Report links observed outcomes to the test cases. Together the documents form the traceability chain top-level requirement → detailed requirement → test case → test result.

• Top-Level Requirements
  • Refinement overview
• Detailed Requirements
  • Integrity detection (SD-TOP-001)
  • Consistent modification (SD-TOP-002)
  • Single-fault recovery (SD-TOP-003)
  • Fault reaction and observability (SD-TOP-004)
  • Timing and execution-context safety (SD-TOP-005)
  • Defensive interface (SD-TOP-006)
  • Self-diagnosis (SD-TOP-007)
  • Requirement overview

Specification consistency

Detailed requirements not refining any top-level requirement (must be empty):

No needs passed the filters

Top-level requirements without refinement (must be empty):

No needs passed the filters